Congested cities stand to benefit the most from switching to electric vehicles, yet they often have the fewest places to charge them. As EVs become increasingly available, the plug problem is finally getting more attention.

Why it matters: Transportation is the leading cause of greenhouse gas emissions in the U.S. Replacing gasoline cars with EVs could go a long way toward helping the planet.

A plug-in is not an easy choice, however, for people who live in apartments or homes without a garage to charge their cars.

• And curbside chargers aren't practical when on-street parking is first come, first served. Plus, many are slow "Level 2" chargers, requiring three to eight hours to fully charge an EV.
• Without widespread access to affordable fast-charging, EVs won't catch on in the places they're most needed, including low-income neighborhoods, where local air quality is typically worse.

What's happening: In New York, several mobility startups are trying to tackle the urban charging dilemma, not just for private EV owners but also for taxis, ride-hailing fleets and delivery vehicles that need to keep running.

• Gravity Mobility, founded in 2021, has developed a compact, fast-charging solution for cramped parking garages. Its first 24-space, fast-charging hub will debut this spring in a garage on West 42nd Street in Manhattan.
• Revel, which rents mopeds and operates a Tesla-based ride-hailing service, opened a 25-plug fast-charging site in Brooklyn last summer.
• Beam Global has deployed 89 of its off-grid, renewable charging pads for New York's municipal fleets. Each charging unit generates and stores its own solar and wind power, without taking up valuable parking spaces.

The big picture: EVs accounted for just 3.5% of U.S. vehicle sales in 2021, according to IHS Markit. With more than 65 new plug-in models coming by 2025, however, there's a race to install charging infrastructure to keep up with the anticipated EV growth.

• The federal infrastructure bill passed last November contained $7.5 billion to install hundreds of thousands more public charging stations. The focus, however, is mostly on highway corridors, not urban areas.
• Leading charging companies like Greenlots, EVgo and Electrify America tend to put banks of chargers near shopping malls and other parking lots where they are visible and easy to access.

Details: Gravity aims to take a different approach with a system that's designed for cramped urban garages and is faster and cheaper than most typical EV charging networks, CEO Moshe Cohen tells Axios.

• The suitcase-sized charger mounts on the floor, wall or ceiling of a garage to operate without sacrificing vehicle parking spaces.
• At 360kW, the device can deliver a faster charge than other equipment on the market, the company says. (Charging times depend on a car's battery capacity and ability to gulp electrons.)
• The system continuously balances the power demand from each vehicle with the demand from other users to smooth out demand on the grid throughout the day.

What they're saying: "This is going to revolutionize the way big cities like New York approach charging infrastructure and the broader transition to clean energy," Cohen said.

The bottom line: For many, home remains the most convenient place to charge. Cities will need to work with developers and building owners to improve charging access for everyone.